Outer cover and image forming apparatus comprising the same

Abstract

An image forming apparatus includes an apparatus body, an outer cover, a conveyance unit, a movable roller, and an interlock mechanism. The outer cover is provided turnably between an outer closing position forming one surface of the apparatus body and an outer opening position in which the one surface of the apparatus body is set openable. The conveyance unit is provided turnably between an inner closing position in which an inside of the apparatus body is set closable and an inner opening position in which the inside of the apparatus body is set openable. The movable roller is pressed by a fixed roller pivotally supported inside of the apparatus body when the conveyance unit is displaced to the inner closing position. The interlock mechanism interlocks an operation of opening the outer cover with an operation of opening the conveyance unit.

What is claimed is: 
     
       1. An image forming apparatus, comprising:
 an apparatus body; 
 an outer cover provided turnably between an outer closing position forming one surface of the apparatus body and an outer opening position in which the one surface of the apparatus body is set openable; 
 a conveyance unit disposed inside of the apparatus body more than the outer cover and provided turnably between an inner closing position in which an inside of the apparatus body is set closable and an inner opening position in which the inside of the apparatus body is set openable; 
 a movable roller pivotally supported by the conveyance unit and being pressed by a fixed roller pivotally supported inside of the apparatus body when the conveyance unit is displaced to the inner closing position; and 
 an interlock mechanism interlocking an operation of opening the outer cover with an operation of opening the conveyance unit; 
 wherein the interlock mechanism comprises: 
 an inner engaging part provided in the conveyance unit and is configured to be turnable between a lock position in which the inner engaging part is locked by an engaged part provided within the apparatus body and an unlock position in which the inner engaging part is unlocked from the engaged part; and 
 an outer engaging part fixed to the outer cover and engaging with the inner engaging part locked by the engaged part when the outer cover is displaced to the outer closing position; 
 wherein the outer engaging part comprises a hook-like claw at a tip extending in a direction from the outer cover to the inside of the apparatus body, 
 wherein the inner engaging part comprises: 
 an engaging body provided turnably centering on an engage turning shaft; 
 a hook part provided continuously from the engaging body and hooked to the engaged part; 
 an interlock part provided projectively from the engaging body and formed so as to be in sliding-contact with the claw of the outer engaging part; and 
 an urging member urging the engaging body toward the lock position; 
 wherein the hook part includes an abutment surface orthogonal to a tangential direction of a turning locus of the conveyance unit passing through a contact point of the engaged part, and 
 the interlock part includes a sliding contact surface bent or curved so as to run along the turning locus of the claw of the outer engaging part turning in a body with the outer cover, 
 the inner engaging part holds the conveyance unit at the inner closing position by resisting against a reaction force received by the movable roller by the hook part's locking with the engaged part; 
 the outer engaging part turns the inner engaging part from the lock position to the unlock position by the claw's relatively sliding with the sliding contact surface of the inner engaging part in a process of turning the outer cover from the outer closing position to the outer opening position; and 
 the outer engaging part is disengaged relatively from the inner engaging part after turning the conveyance unit from the inner closing position to the inner opening position by the claw's relatively sliding with the sliding contact surface of the inner engaging part in a case of turning the outer cover further to the outer opening position after when the inner engaging part is displaced to the unlock position. 
 
     
     
       2. The image forming apparatus according to  claim 1 , wherein an outer turning shaft is formed at a lower end part of the outer cover,
 an inner turning shaft is formed at a lower end part of the conveyance unit, 
 an outer cover turns centering on the outer turning shaft, 
 wherein the conveyance unit turns centering on the inner turning shaft, and 
 the outer turning shaft is disposed under the inner turning shaft. 
 
     
     
       3. The image forming apparatus according to  claim 1 , wherein an inclined surface is formed at a tip surface of the hook part, and
 the engaged part slides relatively on the tip surface of the hook part and turns the inner engaging part which has displaced to the lock position to the unlock position in a process of turning the conveyance unit which has been displaced at the inner opening position to the inner closing position.